Xref: utzoo comp.unix.wizards:18307 comp.unix.ultrix:1777
Path: utzoo!censor!geac!jtsv16!uunet!cs.utexas.edu!mailrus!purdue!decwrl!gilroy.pa.dec.com!klee
From: klee@gilroy.pa.dec.com (Ken Lee)
Newsgroups: comp.unix.wizards,comp.unix.ultrix
Subject: Re: Convert between versions of UNIX
Keywords: UNIX,4.2,Xenix,System V,Porting
Message-ID: <1854@bacchus.dec.com>
Date: 22 Sep 89 17:43:11 GMT
References: <201@fjcp60.GOV>
Reply-To: klee@decwrl.dec.com
Distribution: usa
Organization: DEC Western Software Laboratory
Lines: 18

> I am writing a paper about the problems of converting (porting) software
> between various versions of UNIX, in particular *standard UNIX* System V,
> BSD 4.x, and Xenix.  I have done many ports in many 'directions' but am
> very interested in others' experience.

Rochkind's excellent book *Advanced UNIX Programming* (Prentice-Hall)
discusses porting between various breeds of UNIX.  I assume that other
good UNIX programming books do the same.  The biggest problems are
usually inter-process communication and device drivers, which are 90%
incompatible among most UNIXs.  Signals also bite many people.  Other
differences, like directory searching, file descriptor management, and
utility library differences (e.g., string library) are relatively easy 
to port.

Ken Lee
DEC Western Software Laboratory, Palo Alto, Calif.
Internet: klee@decwrl.dec.com
uucp: uunet!decwrl!klee